Beryllium is the standard currency in spatial grid five three nine.
Source -
Star Trek:Voyager Season 6, Episode 5. Alice -
Neelix holds a bar of pure beryllium.
Seven of nine: "This crystal is beryllium."
Neelix: "Valuable?"
Seven of nine: "Beryllium is the standard currency in spatial grid five three nine. There are species that would trade an entire fleet of starships for this "trinket." – The preceding unsigned comment was added by184.166.212.239 (talk).

That is already mentioned in this article; why are you mentioning it here? 31dot (talk) 20:09, June 11, 2015 (UTC)